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<h2><a name="SECTION0028610000000000000000"></a><a name="atexit-example"></a>
<br>
26.6.1 <tt class="module">atexit</tt> Example 
</h2>

<p>
The following simple example demonstrates how a module can initialize
a counter from a file when it is imported and save the counter's
updated value automatically when the program terminates without
relying on the application making an explicit call into this module at
termination.

<p>
<div class="verbatim"><pre>
try:
    _count = int(open("/tmp/counter").read())
except IOError:
    _count = 0

def incrcounter(n):
    global _count
    _count = _count + n

def savecounter():
    open("/tmp/counter", "w").write("%d" % _count)

import atexit
atexit.register(savecounter)
</pre></div>

<p>
Positional and keyword arguments may also be passed to
<tt class="function">register()</tt> to be passed along to the registered function
when it is called:

<p>
<div class="verbatim"><pre>
def goodbye(name, adjective):
    print 'Goodbye, %s, it was %s to meet you.' % (name, adjective)

import atexit
atexit.register(goodbye, 'Donny', 'nice')

# or:
atexit.register(goodbye, adjective='nice', name='Donny')
</pre></div>

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<span class="release-info">Release 2.5.1, documentation updated on 18th April, 2007.</span>
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